A Greyhound bus traveling to Sacramento from Los Angeles crashed on a highway in California's Central Valley early Thursday morning, killing six and seriously injuring nine others.

The bus, carrying 36 people, struck an SUV that had overturned in front of it, slammed into a concrete center divider and clipped another vehicle shortly after 2 a.m. just outside downtown Fresno, California Highway Patrol Officer Axel Reyes said. It went off the right shoulder of the highway down an 15-foot embankment, hit a eucalyptus tree and came to rest on a freeway off-ramp with its front end smashed and tree branches jutting into the vehicle.

Twisted pieces of metal, broken glass and torn clothing littered the ground around the bus wreckage.

Arlen Snider, who had been traveling from Phoenix to Sacramento to visit his mother, said he was asleep in the middle section of the bus when the crash occurred. He awoke to the smell of smoke and injured passengers all around him.

"I woke up on the floor of the bus and started helping people off the bus," Snider, who escaped uninjured, said after arriving in Sacramento's bus terminal Thursday morning.

The six dead included four women and two men. Nine people were taken to the hospital with moderate to critical injuries, Reyes said. The bus driver was among the dead.

"I had just woke up and I heard a boom once, and a boom again and the next thing I know we were down this embankment," Linda Gee, a passenger on the bus, told KMPH-TV in Fresno.

"I'm alive and I thank god I'm alive," she said. "There was just bleeding everywhere."

The blue Chevy Trailblazer that had overturned in the fast lane also landed at the bottom of the embankment, its roof caved in and doors crushed.

Officials were investigating the cause of the initial SUV crash, including whether it was related to drunken driving, Reyes said.

The bus departed Los Angeles late Wednesday and stopped in Fresno before continuing on its route to Sacramento with 35 passengers on board, said Greyhound spokeswoman Bonnie Bastian. It was on its way to Madera for one of about eight scheduled stops when the crash occurred.

A relief bus was sent to take nine passengers who wanted to continue on to their destinations.

The two northbound lanes of Highway 99, a major route through the San Joaquin Valley, were closed for several hours after the crash.

---

Associated Press writers Judy Lin in Sacramento and Sudhin Thanawala in San Francisco also contributed to this report.